<!DOCTYPE HTML>
<html>
<head>
  <meta charset="utf-8">
  <title>默认行为</title>
   <style>
      *{margin:0;padding:0;list-style:none;}
      #div1{position:absolute;width:80px;background:#CCC;border:1px solid black;display:none;}
   </style>
   <script>    /*默认行为：浏览器自带行为，例如:右击页面，会有一个小菜单*/
	 document.oncontextmenu=function(ev){
	       var oEvent=ev||event;
		   var oDiv=document.getElementById("div1");
		   oDiv.style.display="block";
		   oDiv.style.left=oEvent.clientX+'px';
		   oDiv.style.top=oEvent.clientY+'px';
	 	   return false;//普通阻止默认行为方法
	 };
	 document.onclick=function(){
	    var oDiv=document.getElementById("div1");
		oDiv.style.display="none";
	 };
   </script>
</head>
<body>
   <div id="div1">
     <ul> 
	    <li>aaa</li>
        <li>bbb</li>
		<li>ccc</li>
		<li>ddd</li>
     </ul>  
   </div>
</body>
</html>